A conference of government delegations, called the United Nations Conference on
Environment and Development was held in Rio in 1992.

The conference yielded five documents signed by heads of state: the "Rio Declaration," a statement of broad principles to guide national conduct on environmental protection and development; treaties on climate change and biodiversity; a statement of forest principles; and "Agenda 21," a document presenting detailed workplans for sustainable development.

Discussion of a convention on climate change began in 1988 with the establishment of the Intergovernmental Panel on Climate Change (IPCC), an advisory body of scientists and officials that assessed climate science, impacts, and response strategies.

Discussions, however, stalled between the United States and other industrialized countries, particularly those of the European Community, which argued that the convention should contain specific commitments to limit emissions of carbon dioxide to 1990 levels by 2000. The United States argued that such limits were premature and lacked sufficient scientific evidence.